1. From humble beginnings
Plant an acorn and grow a mighty oak. If you see an oak plantation in Europe or America, these trees will most likely end up as whisky casks.
2. A visit to the cooperage
Once grown and felled, it’s time to visit the cooperage. Here, the tricky ancient art of coopering – AKA cask making – sees the wood transformed into staves and bevelled, jointed, shaped, hammered and raised to create the finished product. ‘Cask’ is the catchall term used to describe barrel-shaped vessels of all sizes.
3. Bourbon, sherry, rum & wine
The majority of casks are first used to house other liquids such as bourbon, sherry, rum and wine before being moved on to whisky distilleries. The colour, aroma and flavour of the whisky is shaped and influenced by the cask; particularly if the wood has been seasoned by previously coming into contact with another type of spirit, such as bourbon.
4. To the distillery!
Bourbon barrels, rum casks and sherry butts are among distillers’ favourite vessels for maturing whisky. Virgin oak casks impart more tannins and strong vanilla aromas, which is why second hand casks, which offer milder flavours, are generally preferred.
It’s estimated there are more than 20 million casks in Scotland; that’s four casks to every one person! In most cases, distilleries char the interior of the cask which ‘activates’ the wood; helping to speed up the interaction between the whisky and the wood that imparts smoky flavours, sweetness and colour from the oak.
5. Three is a magic number
Whisky casks are usually used up to three times after which point the wood becomes saturated with whisky. This isn’t the end of the road however, with craft brewers and cider makers keen to pick up used whisky casks to impart flavours and aromas to their own products. And so the cycle begins again!